Reversing turbine



Nov. 20, 1923. 1,474,351

W. B. FLANDERS REVERS ING TURBINE Filed May 13, 1920 IN VEN TOR.

43.51axndud ATTORNEY Patented Nov. 253 i923.

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WARREN B. FLANDERS, OF ESSINGTON, PENNSYLVANIA, ASSIGNQR TO IVESTING HOUSE ELECTRIC AND MANUFACTURING- CQMPANY, A GORPORATIQN OFTPENN- I SYLVANIA.

Application filed May 13,

T aZZ w/ om it may concern.

Be it known that I, WARREN B. FLANonRs,

a citizen of the United States, and a resident of Essington, in the county of Delaware 5 and State of Pennsylvania, have invented a new and useful Improvement in Reversing Turbines, of which the following is a specification. p

, My invention relates to turbines of the marine type having ahead and reversing sets of blading, and has'forrits object to provide an extra row of blades, carried by the stator element, for one set of blading in order to direct steam discharged from the latter with a, component of motion in the direction of rotation of the rotary element,

thereby avoiding braking and churning action of the steam and diminishing the liability "of the turbine to overheat, es-

pecially when the reversing set is operative. Another object of the invention is to provide a turbine having the ahead and reversing blading, adapted to discharge into a common chamber, one oi the sets of blad- .ing being preferably of the impulse type .and provided with an additional row of blades carried by the stator to direct the discharge in the direction of rotation of the rotor.

In the drawings, Fig. 1 is a longitudinal sectional view of a turbine having a reversing section; Fig. 2 is a diagrammatic view showing the relationship of nozzles and blading; and Fig. 3 is a velocity diagram to show the velocity of steam as it traverses the different rows of blades of the impulse element. 4 p

In turbines of the marine type,the reversing section usually contains few elements or rows of blades in comparison with the elements or rowsofblades of the ahead section, so that the ratio o'f'steam velocity to wheel or blade velocity is much greater, and the steam will leave the last row of blades with a high velocity. Where the last row of blades of the reversing "section is a moving one, the steam is discharged with a component of motion which is in a direction opposedto that of the rotor, giving a high relative velocity of the rotor and the steam and thereby developing friction, the work of which opposes rotation of the rotor and vis likely'to produce sufficient heat topr ove to be injurious 3 Also exhaust steam may BEVERSING TURBINE.

1920. Serial No. 381,138.

this way, instead of developing -friction which opposes the rotation of the rotor, would, if it develops any friction due to relative movement, produce a moment which assists the rotation of the rotor. f

In the drawings, I show a turbine of the I marine type having an ahead section 5 and a reversing or astern section 6 including bladlng carrled by the rotor element 7 and the stator element 8. The ahead section is provided with the usual steam inlet andthe steam, after traversing and giving up its energy to the rotor blades, is discharged into the chamber 10 between th'eahead and astern blading.

The astern blading is preferably of the I impulse type and is provided with the usual two rows of blades 13 and 15carried by the rotor 7, and with an intervening row of stationary blades 14 carried the stator 8. The stator is preferably provided with a series of nozzles 12 adapted to discharge into the first row of moving blades 13. In addition to the ordinary arrangement of blad-.

ing, I provide an 'Qadditional row .of stationary blades 16 carried by the stator which are adapted to receive steam discharged by the last row of moving blades 15, and to direct'it into the space 10 in the same direction as the direction of rotation of the rotor. A consideration of the directions of rotation of the rotor and the arrangements of blading for the ahead-astern sectionswill show that steam from one section leaves-the stationary blades 16 in a direction toward the backs of the last row of blades 11 of the other section. Since the steam is moving" in the same general direction as the rotor, and at a higher velocity than the rotor, it is obvious that the blades 11 will not act as braking elements for the steam. discharged. Also, it will be seen that, dueto the'direction of the discharge of steam'by the blades 16 in the same direction as the direction of rotation ofthe rotor, there will be no relative opposed motions of the rotor and the steam, whereby frictional losse and objectionable heat are developed.

Fig. 2- shows in a diagrammatic way how the steam passes through the impulse section. Steam enters through the nozzles 12, is expanded and discharged at high velocity against the moving impulse blades 13. Part of the velocity of the steam is abstracted by the blades 18 and the steam is discharged into the stationary row of blades M and is there redirected and discharged into the moving row of blades 15 which abstract more of the velocity or the moving steam. The steam is discharged from the last row ofmoving blades 15 through the stationary blades 16 and is thereby redirected so that its direction of motion has a substantially large component in the same direction as the direction of rotation of the rotor. Dotted lines Z) from the stationary blades 16 indicate 7 the direction of flow of steam therefrom and dotted lines a from the moving row of blades 15 also indicate the direction of motion of steam discharged therefrom. It

will be apparent, from the dotted lines a and b and the direction of the rotation of the rotor, that when steam is discharged against the direction of rotation of the rotor, objectionable heating effects are developed, possibly resulting in, injury to the blading. However, when the" discharge is along the lines Z the discharged steam has a large component of motion in the direction of motion of the rotor, and thereby avoids the development of objectionable heat on account of friction.

Fig. 3 shows diagrammatically the decrease in velocity as the steam passes through the difierent rows of impulse blades. If it is assumed that steam is discharged from the nozzles 12 at a velocity of 3300 feet per second, it will leave the moving row of 'blades 15 at a velocity of approximately 1300 feet per second and will be redirected and discharged with an approximate velocity of 1200 feet per second in the direction of rotation of the rotor. By reason of the high velocity of the steam discharged by the stationary row of blades of the section 6, as well as the direc tion of discharge, the steam is actually kept from entering the rows of blading of the section 5 and therefore greatly reduces the loss in the latter when the section 6 is in operation. This is further facilitated due to the fact the backs of the lastrow of blades of the inoperative section are opposed to the direction of discharge and serve to deflect the steam.

Fromthe description of my invention as 4 abovev set'forth, the operation thereof will be obvious. When it is desired to render opersa e the section 6, steam is admitted to the nozzles 12, is expanded and discharged the steam with" the rotor would actually be an assistance to the rotor.

While I have shown my invention in but one form, it will be obvious to thoseskilled in the art that it isnot so limited, butis susceptible of various other changes and modifications, without departing from the spirit thereof, and I desire, therefore,that only such limitations shall be placed thereupon as are imposed by the prior art ora's are specifically set 'forth' in the appended claims. 7

What I claim is p p r 1. In a reversing turbine, the combination of an ahead blading set and a. reversing blading set having opposed exhaust ends and a series of blades cooperating'with one set to insure the discharge of'steamthere- 1forom in the direction of rotation of the turine.

2. In a turbine, the combination or two sets of blading adapted to exhaust in opposite axial directionsinto a common exhaust chamber, of a row of stationary blades cooperating with the last row of moving blades of one set of blading for directing the motive fluid to the exhaust chamber with a component of motion in the direction of rotation of the turbine. I

3. In a turbine, the combination of two sets of blading adapted to exhaust in opposite axial directions into a common exhaust chamher, one of said sets of blading being of the impulse type, of a row of stationary blades for changing the direction ofthe motive the rotor and the stator thesets of blading having opposed exhaust ends and adapted to discharge into a common space therebetween, and a row of redirecting blades associated with one of said sets so as to redirect the discharging elastic fluid with a component of velocity in the directionof rotation of the rotor. V

5. In a reversingturbine of the marine type,tl1e combination ofa rotor and a stator, an ahead element comprising bladingfcan 1,474,351 I I I I 3 ried by the rotor and the stator, a reversing ment to redirect the elastic fluid so as to element comprising blading of the impulse have a component of velocity in the direc- 10 type carried by the rotor and the stator, the tion of rotation of the, rotor, 1 exhaust ends of the ahead and reversing ele- In testimony whereof, I have hereunto ments being opposed and adapted to dissubscribed my name this 12th day of May, charge into a common space, and a roW of 1920.

stationary blades cooperating with the last I row of impulse blades of the reversing ele- WARREN B. FLANDERS. 

